Electric components are used in a wide range of applications. In many applications it is necessary to protect the electric components from the environments in which they operate. For example, electric components used in environments with high humidity need to be protected from this humidity to prevent corrosion of their electrical connections. Typically, electric components are protected by sealing them within a ceramic or semiconductor package.
FIG. 1A depicts a prior art ceramic package 102 for protecting electric components. An electric component 100 is packaged by attaching the electric component 100 to a base 104 made of a ceramic material and, then, attaching a lid 106 having a cavity 108 for accommodating the electric component 100 to the base 104 with a sealing material 110. Connections for control and input/output (I/O) signals are made to the electric component 100 from outside the package 102 through electrical leads 112 that extend along the surface of the base 104 through the sealing material 110 between the base 104 and the lid 106. Since the electrical leads 112 extend through the sealing material 110, the sealing material 110 must be non-conductive and, therefore, conventional soldering techniques cannot be used to attach the lid 106 to the base 104.
The lid 106 has a surface area that is smaller than the surface area of the base 104 to provide a suitable planar bonding area 114 on the exterior of the package 102 for facilitating contact with the electrical leads 112. Since the surface area of the lid 106 is smaller than the surface area of the base 104 (and accommodates the electric component 100), the base 104 has a relatively large footprint in relation to the electric component 100. This may be undesirable if a small form factor or a low cost is desired.
In addition, each ceramic package 102 is produced individually using expensive hybrid assembly techniques, rather than inexpensive, mass production, wafer level techniques. Also, ceramic packaging is expensive due to the high cost of raw ceramic material used to create the base 104 and lid 106. Thus, ceramic packaging may be cost prohibitive.
FIG. 1B depicts an alternative prior art ceramic package 116. In this package 116, metallic ink traces 118 are printed on a base 104 made of a ceramic material to provide connections for control and I/O signals. Ceramic side walls 120 are then added to the base 104 over the metallic ink traces 118. The electric component 100 is packaged by attaching the electric component 100 to the base 104 and, then, soldering a lid 106 made of a metallic material (or a ceramic material with a metalized seal ring) to the side walls 120. The metallic ink traces 118 have an inherent high resistivity that may make the ceramic package 116 unsuitable for certain applications. In addition, as in the previous ceramic package 102, this ceramic package 116 requires a base 104 with a relatively large footprint and uses expensive materials and hybrid assembly techniques.
FIG. 1C depicts a prior art semiconductor package 122 having a base 104 made of semiconductor material and a lid 106 made of semiconductor material. The lid 106 is attached to the base 104 using frit glass 124 (i.e., a powdered glass held together in a slurry). The electric component 100 is packaged by attaching the electric component 100 to the base 104, depositing a layer of frit glass 124 on the base 104, attaching the lid 106 to the frit glass 124, and curing the frit glass 124 to produce a sealed semiconductor package 122. Connections for control and I/O signals are made to the electric component 100 from outside the package 102 through electrical leads 112 that extend along the surface of the base 104. As in the previous techniques, the semiconductor packaging technique requires a base 104 with a relatively large footprint. In addition, the temperatures required to cure the frit glass 124 may be damaging to certain electric components.
The semiconductor package 122 may be mass produced using wafer packaging techniques. After the package 122 is produced, however, the lid 106 has to be etched precisely to expose a planar bonding area 114 without damaging the electrical leads. This additional step adds complexity, thus increasing production costs.
Accordingly, there is a need for electric component packages and a method for producing electric component packages that overcome the above limitations. The present invention fulfills this need among others.